Actinic keratoses (AK) are common cutaneous lesions associate with chronic ultraviolet radiation exposure. While most authorities consider AK as a pre-malignant lesion, some consider it as an incipient squamous cell carcinoma (SCC). In addition, the skin around clinically obvious AK lesions has been subject to the same chronic ultraviolet exposure, resulting in genetic damage and mutations, resulting in "field cancerization." Subclinical AKs may progress to clinical AKs, or even de novo invasive SCCs.